CSA mine at Cobar

Client: CSA Mine, Cobar

Project: Shaft No 1 Headframe Refurbishment

Description: Refurbish the 80-year-old head frame so it can be used again to haul mine ore and personnel from a kilometre below the mine's surface

Barnson’s Role: Data capture and three dimensional structural modelling of the existing structure, concrete testing and geotechnical investigation of existing footings

Time frameAwaiting funding and final design


The existing head frame at CSA's Cobar mine was originally built on another site in 1936. It has been on the current mine lease since 1965 but has been unused for the past 15 years while the existing mine shaft (No 1) has only been used for air cooling.

Barnson was engaged to undertake the data capture and three dimensional structural modelling of the head frame, test the concrete and undertake a geotechnical investigation of the existing footings. The aim of this project was to design the refurbishment of the head frame so that it could be used again to haul mine ore and personnel from more than a kilometre underground to the mine's surface.

With such an old structure, the first issue was safety and ensuring the head frame was capable of withstanding repeated use over a 10-year mine life. Barnson initially undertook a fatigue analysis to determine what additional strengthening was required so the head frame could cope with the expected number of cycles.

Part of the project involved three-dimensional structural modelling of the existing frame to determine its capacity. Then the team had to design the structural strengthening to increase the load capacity of the head frame. This included modelling and upgrading the design of the footings, based on a geotechnical investigation and concrete coring results. 

One of the biggest challenges of the project was the age of the drawings, which did not incorporate later modifications to the structure. After an inspection, the team put the structure into a three dimensional Cad model, then exported the model into structural software for analysis. The compatibility of the two software systems worked well and proved that the initial challenges of a task can easily be overcome when you have access to the right equipment.